Safety brake device and method for safety braking of an autonomous vehicle

Patent metadata

Field	Value
Publication number	US-2017015291-A1
Application number	US-201615202930-A
Country	US
Kind code	A1
Filing date	Jul 6, 2016
Priority date	Jul 13, 2015
Publication date	Jan 19, 2017
Grant date	—

Abstract

Disclosed herein are a safety brake device and method for safety braking using a hydraulic brake system including hydraulic wheel brakes of an autonomous vehicle, the autonomous vehicle further having an electrical power supply and signaling system for enabling an autonomous drive mode. The method comprises pressurizing a pressure storage canister containing brake fluid, monitoring electrical power supplies and signaling of the autonomous vehicle, and releasing brake fluid into the hydraulic brake system of the autonomous vehicle to activate the wheel brakes thereof upon determining loss of at least one of electrical power and signaling of the autonomous vehicle. Disclosed herein is also an autonomous vehicle comprising a safety brake.

First claim

What is claimed is:

1 . A safety brake device adapted for a hydraulic brake system including hydraulic wheel brakes of an autonomous vehicle, the autonomous vehicle further having an electrical power supply and signaling system for enabling an autonomous drive mode, the safety brake device comprising:
a pressure storage canister adapted to contain brake fluid; an electrical power and signaling connector connectable to the electrical power supply and signaling system of the autonomous vehicle; a supervisor electronic control unit (ECU) for monitoring electrical power supply and signaling of the autonomous vehicle; a pressure pump connected to the pressure storage canister via an inlet valve; a hydraulic brake system connector connected to the pressure storage canister via a pressure application valve and connectable to the hydraulic brake system of the autonomous vehicle; wherein the pressure pump, the inlet valve and the pressure application valve are adapted to be controlled by the supervisor ECU, and wherein the supervisor ECU is configured to open the pressure application valve to release brake fluid into the hydraulic brake system of the autonomous vehicle to activate the wheel brakes thereof upon determining loss of at least one of electrical power and signaling of the autonomous vehicle.

2 . The safety brake device according to claim 1 wherein the supervisor ECU further is operable to selectively open the inlet valve and operate the pressure pump to apply pressure to the pressure storage canister for pressurizing brake fluid contained therein.

3 . The safety brake device according to claim 1 wherein the supervisor ECU further is configured to monitor the pressure available in the pressure storage canister.

4 . The safety brake device according to claim 3 wherein the supervisor ECU further is configured to prohibit engagement of the autonomous drive mode of the autonomous vehicle when connected to the safety brake device unless a predetermined pressure is available in the pressure storage canister.

5 . The safety brake device according to claim 4 wherein the supervisor ECU further is configured to selectively open the inlet valve and operate the pressure pump when the autonomous vehicle is in the autonomous drive mode to apply pressure to the pressure storage canister in order to maintain at least the predetermined pressure in the pressure storage canister pressurizing brake fluid contained therein.

6 . The safety brake device according to claim 1 further comprising a drainage valve connected to the pressure storage canister, wherein the supervisor ECU further is configured to open the drainage valve when exiting the autonomous drive mode of the autonomous vehicle to drain pressure from the pressure storage canister for de-pressurizing brake fluid contained therein.

7 . The safety brake according to claim 6 wherein the supervisor ECU further is configured to open the inlet valve in reverse while the pressure pump is inactive or operated in reverse to assist in draining pressure from the pressure storage canister for de-pressurizing brake fluid contained therein.

8 . A method for safety braking an autonomous vehicle using a hydraulic brake system including hydraulic wheel brakes of the autonomous vehicle, wherein the autonomous vehicle further has an electrical power supply and signaling system for enabling an autonomous drive mode, the method comprising:
pressurizing a pressure storage canister containing brake fluid; monitoring electrical power supply and signaling of the autonomous vehicle; releasing brake fluid into the hydraulic brake system of the autonomous vehicle to activate the wheel brakes thereof upon determining loss of at least one of electrical power and signaling of the autonomous vehicle.

9 . The method according to claim 8 wherein a pressure pump is connected to the pressure storage canister via an inlet valve, and the method further comprises selectively opening the inlet valve and operating the pressure pump to apply pressure to the pressure storage canister to pressurize brake fluid contained therein.

10 . The method according to claim 8 further comprising monitoring pressure available in the pressure storage canister.

11 . The method according to claim 10 further comprising prohibiting engagement of the autonomous drive mode of the autonomous vehicle unless a predetermined pressure is available in the pressure storage canister

12 . The method according to claim 11 wherein a pressure pump is connected to the pressure storage canister via an inlet valve, and the method further comprises selectively opening the inlet valve and operating the pressure pump when the autonomous vehicle is in the autonomous drive mode to apply pressure to the pressure storage canister to maintain at least the predetermined pressure in the pressure storage canister for pressurizing brake fluid contained therein.

13 . The method according to claim 8 further comprising opening a drainage valve when exiting the autonomous drive mode of the autonomous vehicle to drain pressure from the pressure storage canister and de-pressurize brake fluid contained therein.

14 . The method according to claim 12 further comprising opening a drainage valve when exiting the autonomous drive mode of the autonomous vehicle to drain pressure from the pressure storage canister and de-pressurize brake fluid contained therein.

15 . The method according to claim 14 further comprising opening the inlet valve in reverse while keeping the pressure pump inactive or operated in reverse to assist in draining pressure from the pressure storage canister and de-pressurizing brake fluid contained therein.

16 . An autonomous vehicle comprising:
a hydraulic brake system including hydraulic wheel brakes; an electrical power supply and signaling system for enabling an autonomous drive mode; and a safety brake device according to claim 1 .

Assignees

• Volvo Car Corp

Inventors

• Kindberg Leif

Classifications

• B60T7/12 Primary

  for automatic initiation; for initiation not subject to will of driver or passenger {(limiting speed of vehicles other than rail vehicles B60K31/00)} · CPC title

• B60T11/103 Primary

  in combination with other control devices (conjoint control of brake system and at least another sub-unit B60W10/188) · CPC title

• B60T8/1701

  Braking or traction control means specially adapted for particular types of vehicles (for vehicles having more than one drive axle B60T8/1769) · CPC title

• B60T11/26

  Reservoirs (integral with master controls B60T11/22) · CPC title

• B60T11/28

  Valves specially adapted therefor (recuperation valves B60T11/232) · CPC title